Shanghai is a big metropolis with 23 million people in China. Serving safe drinking water to the public is not only related to public health but also crucial for social stability. There are abundant studies from the technical aspect to detect water quality, but not much sight given to the public attitude. Trust is fundamental to social relationships as an important social capital. Via reviewing related literatures we summarized how trust being studied, especially within resources management area and the conceptual and empirical difference between China and the world. Then, we use Shanghai as our study case area. Through analysis of demographical factors and information flow, the study aims to measure public trust levels to different institutions that release information about water quality for daily water use and water crisis, and investigate the vital factors that shape public trust levels about drinking water quality in Shanghai. Then through a reasonable but may be not impeccable explanation to the results, we hope to pave a way for constructing effective municipal administration.